Flood control and drainage facilities affording positive storm water disposal shall be designed and provided by the subdivider. The subdivider shall construct any drainage facilities that may be necessary to protect property within and affected by the subdivision. If, in the opinion of the Director ofPublic Works, it is impracticable to construct drainage facilities at the time of the construction of other subdivision improvements, or the construction of such drainage facilities may be deferred until a date subsequent to the construction of other improvements, the subdivider may, in lieu of constructing such drainage facilities, pay to the County of Humboldt the estimated costs, as determined by the Director of Public Works, of the construction of such drainage facilities.

Drainage facilities referred to herein are such drainage facilities as are shown on the current adopted drainage plan for the drainage area in which the subdivision is to be located. Said drainage plan shall contain an estimate of the total cost of constructing the local drainage facilities and a map of the drainage are showing its location and the type and location of proposed drainage facilities.